A flood of migrants from Romania and Bulgaria is unlikely – but those arriving will find housing services unable to help. Photograph: Valentina Petrova/AFP/Getty Images

The next wave will not be a repeat of 2004. The real risk is that low-paid immigrants could be forced to live on the streets.

An official petition to halt the free entry of Bulgarians and Romanians into Britain from January next year has already gained 130,000 signatures. Fuelled by projections that as many as 250,000 might arrive by 2019, and by ministers equivocating on whether it they have received estimates or not, there are now belated moves to review the free movement rules.

This could almost be an object lesson in how not to prepare for a new wave of migrants, and of failing to learn from the first EU expansion in 2004. It all presupposes that there will be a wave of immigration, and that if there is that it will put pressure on housing and other public services. Is this actually likely to happen?

The controversy first broke when communities secretary Eric Pickles was interviewed in January, hinting that government estimates over the number of migrants to expect from these countries did exist. Presumably this triggered the release of new forecasts from Migration Watch a few days later, predicting additional immigration of 50,000 people per year, based on the events of 2004. But this comparison is highly questionable.

Only Britain, Ireland and Sweden allowed entry to new EU nationals in 2004, so the pent-up desire to move countries was strongly focused on the UK, to which Poland in particular had historic ties. A more appropriate comparison, suggested by Sue Lukes of MigrationWork, is with what happened when Germany finally dropped its restrictions in May 2011: immigration barely increased because most of the people who wanted to move had already done so, and the economic situation was by then very different to that in 2004.

Second, Bulgarians and Romanians have had freedom to move to several countries since 2007: three million have already migrated to Italy, Spain and elsewhere. From 2014 they can go anywhere in Europe. Even though UK restrictions were partially lifted six years ago, only around 100,000 have moved here since. Why would Britain suddenly become more popular, especially when most established Bulgarians and Romanians live in London where it is now extremely difficult to find somewhere to live?

Bearing in mind the Migration Observatory‘s warning that there is no sound method for calculating a reliable figure, the suggestion by the Romanian ambassador that the yearly total might be nearer 10,000 than 50,000 seems a far more likely guess.

But even if the figures are lower than the scare stories suggest, will the newcomers affect housing demand? Obviously, the simple answer is yes, because any arrivals are bound to look for accommodation.

But given that skilled or self-employed nationals from these countries can already work in Britain, any new attraction is likely to be to low-paid workers. Indeed, many Bulgarians and Romanians have already been here seasonally, doing farm work, and this seems likely to continue.

The typical pattern has been people coming without their families to work for a short time, often accommodated by employers or gangmasters. They’ve had only limited impact on the overall housing market (although local impacts in places such as Peterborough have been greater).

It is however a huge step for Bulgarians and Romanians in private lettings to gain a social housing tenancy. Many are here for a short time or are mobile, so they rely on accommodation arranged for them. Most have poor English or are unaware of their housing rights or how to exercise them (as agencies advising migrants will readily testify). Regrettably, that uncertainty can extend to frontline housing staff who may simply assume they are ineligible for housing support.

If applicants are childless, they are unlikely to get priority; those with children face a long wait in most areas. Almost 10 years since the EU expanded its borders to the east, less than 4% of new social housing lettings go to nationals from the new EU states. Given pressures to respond to the bedroom tax and other welfare changes, available lettings to new tenants are likely to fall anyway, making their chance of success even smaller.

Nevertheless, Pickles has responded by looking to see if councils should be required to do more to restrict social housing to those with a long local connection. There are also moves to tighten the habitual residence test which determines eligibility of European nationals for many benefits, but it would be surprising if either had much effect. Some councils, such as Hammersmith and Fulham, have adopted stricter residence tests already, and while all are now entitled to do so in practice, the pressure of demand is such that the tests are likely to make only a marginal difference to allocations.

Altering the entitlements of EU nationals to wider benefits is fraught with problems because it depends on the interpretation of both UK and EU law. The government has recently come a cropper in the so-called Zambrano case, and is by no means the first government to do so.

More worrying is the potential for Bulgarians and Romanians to lose low-paid or insecure jobs, or for other reasons to end up sleeping rough. Among non-British nationals, Romanians in particular already figure strongly in the regular street counts carried out by Broadway, a homelessness charity in London. So the main pressure on housing providers may well not be on conventional social landlords, but on the limited numbers of charities who provide accommodation and subsistence for those who are deprived of help by the complex rules and the barriers described here.

Of course, if eligibility rules stay as they are, there is every chance that rough sleeping among Bulgarians and Romanians will start to decline next year, as it did for nationals of the other new EU member states after they became fully entitled to benefits in May 2011. This is the real risk if the government succeeds in altering the rules: it will have little effect on social housing demand, but may push more people onto the streets.